Method of regulating the velocity of fumes passing through electrical precipitators



w. w. mom,

METHOD OF REGULATING THE VELOCITY OF FUMES PASSING THROUGH ELECTRIC/HQPRECTPITATORS. APP LICATTONJiLED SEPT 25, 19m.

1,337,489. Patented Apr. 20, 1920.

gnvewfoz 2mm mils 'UTED STATES PATENT OFFICE.

WILLIAM W. STRONG, OF MEOI-IANICSBUBG, PENNSYLVANIA, ASSIGNOR T0RESEAROH CORPORATION, OF NEW'YORK, N. Y., A CORPORATION OF NEW YORK.

I METHOD OF REGULATING THE VELOCITY 0F FUMES PASSING THROUGH ELECTRICALrnncrrrrnrons.

Specification of Letters Patent.

Patented Apr. 20, 1920.

Application filed September 25, 1917. Serial No. 193,207.

To all whom it may concern:

Be it known that I, WILLIAM W. STRONG, a citizen of the United States,residin at Mechanicsburg, in the county of Cum erland and State ofPennsylvania, have invented certain new and useful Improvements inMethods of Regulating the Velocity of Fumes Passing'Through ElectricalPreci itators, of which the following is a .speci cation.

The present inventionrelates to electrical precipitators.

It is found in practice that gas passing through electrical treaterpipes has different velocities in difierent'regions of thecrosssectional area thereof. The velocity of the fumes or gases isusually greatest near the periphery of the pipes.

Onthe other hand. arranged in multiple and gas is passed therethrough.it is found that difierent quantities of gas Will pass at differentvelocities through the different pipes.

' The object of my invention is to provide means for equalizing the flowof gas in different pipes or in different regions of a single pipe.Ordinary dampers cannot be used in the ordinary way on account of thehigh potential difference between the discharge electrode and the pipewhich is the collecting electrode. It is absolutely necessary that thedielectric be uniform throughout'the pipe to produce a uniform silentdischarge.

In order to make it possible to place dampers in the pipes foraccomplishing the object of my invention, I provide means whereby thecritical point of disruptive discharge is raised to the same extent thatit is lowered by the introduction of the dampers. In my preferredembodiment I provide an electric gap along the discharge electrode inthe form of an insulator link adapted to mechanically interconnectsections of the discharge electrode. By this provision dampers may beplaced in the pipe without causing a spark-over or disruptive dischargeat voltages below thenormal critical voltage.

For a fuller understanding of my invenhen treater pipes are tion I referto the appended drawings in which:

Figure l is a sectional view of a treater pipe embodying my invention;

' Fig. 2 an elevation of another form, partly in section to show theapplication of my invention;

Fig. 3 a diagrammatic view of the electrical arrangement;

Fig. 4 a transverse section on line 4-4: of Fig. 1; and

Fig. 5 is a plan view of a treater pipe and damper mechanism.

In Fig. 1, 1 represents a treater pipe of the usual type constitutingthe collecting electrode and 2 the discharge electrode. The potentialfor the charging current is so chosen in practice that it produces amaximum of silent discharge without spark-over. The potentialis.therefore, kept just below the point where disruptive discharge takesplace. The pipe and the discharge electrode must be as uniformly smoothas it is possible to make them in order to produce this maximum silentdischarge and the highest possible degree of efficiency. Any slightprojectionon either of the electrodes leads to premature disruptivedischarge. It is. therefore, easily seen that it is-not possible toplace dampers or constrictive means of any descriptionwithin the pipe orflue without lowering the critical point of disruptive discharge inproportion.

In order to admit of the application of dampers. or constrictions in thepipe and at the same time prevent a disruptive discharge I provide aninsulator link 3. This link 3 serves the purpose of mechanically interconnecting the sections 4 and 5 of the discharge electrode 2 withoutproducing an electrical field thereby. The funnel-shaped shield orscreen 6, which is made of insulating material, has its base inengagement with the wall of the pipe 1 and extends toward the insulatorlink 3. The object of this screen is to force the gas ascending in thetreater chamber or pipe 1 into contact with or in close proximity to theelectrode 2 to be charged thereby. By this arrangetoward the electrode'ment the gas ad'acent the Walls of the cham-" her, which wit out itwould travel at a greater velocity along the. walls and might escapetreatment, is forced out-of its course and .is together with the othergas, directed 2 and thereby subjected to the action of the intenseelectrical field 7 immediately surrounding the electrode;

Since the insulator 3 does not produce an electrical field, the shieldor screen 6 may approach it closely without causing a spark- "over.

' 3, the electrode 2 may be enlarged to increase the surface area, asindicated at 9, and thereby raise the critical point to compensate forthe lowering of the critical point incident to the introduction of thering 'Z. The gas traveling along the walls of the pipe or c amber 1 isthereby forced inwardly into an intense corona field set up between theenlargement 9 and the ring 7.

While this arrangement may be used in place of the screen 6 and theinsulator link 3, it may be used in addition to it, as indicated.

Fig. 2 represents a precipitator of. the multiple pipe treater type inwhich dampers 10 and 11 are placed within treater pipes 12 and 13 forthe purpose of automatically 8%:lfill2ll1g the rate of flow of the gastherein T e dampers l and 11, which form part of my invention describedin my copending application Ser. No. 193206, filed Sept. 25,

' 1917, have the form of semi-circular disks of insulating materialprovided with semicircular recesses and 11 which separate the dampersfrom the insulator links lei and 15 respectively, which interconnect theelectrode sections and 21. The dampers, one of which is shown on alarger scale in Fig. 5 may he journaled by. means of pivots 22 in thewall of the pipe 12. At one side the pivots 22 project beyond the outerface of the pipes and are connected to cranlr arms 23 and 2%. At theouter ends the crank arms are provided with arms or levers 25 and 26formed on their upper faces with ribs 27.

. These ribs serve the purpose of adjustably supporting a weight pocket28. Like in the device shown in Fig. 1, the insulator links electricfield and make it feasible to lace the dampers within the tube about theelectrode. The dampers are preferably placed at the/upper end oil thepipes to prevent a deposit therein as much as possible. I

The insulating link may he placed anywhere in the pipe chamber. itslocation depending merely on the location or the damper or constriction.As shown in Fig.

ondary 16 of a transformer 17 and is rectified by a rectifier 18.

I claim 5 1. In an electric precipitator the combination of a treaterchamber, a. constriction in the chamber, a discharge electrode extendingthrough the'chamber and the constriction and means on the electrode forpreventing a disruptive discharge to said constriction at voltages belowthe normal critical voltage of the precipitator.

2. In. an electric precipitator the combination ofa treater chamberhaving a constricted portion, a discharge electrode extending throughthe chamber and the constricted portion, and means for finalizing thecritical point of disruptive discharge substantially uniform throughoutthe length of the chamber.

3. In an electric 'precipitator the combination of a treater chamber, adischarge electrode extending therethrough, means for directing the gaspassing through the chamber into regions adjacent the dischargeelectrode and means for making the critical point of disruptivedischargesub stantially uniform throughout the chamher.

- l. lnan electric precipitator the comhination of a treater chamber, adischarge electrode extending therethrough, means for constricting theflow of gas adjacent the electrode and means for preventing a disruptivedischargeirom the discharge electrode to said constricting means atvoltages below the normal critical voltage.

5. in an electric precipitator the cornhination of a treater chamber ofsubstantially uniform cross-section throughout its length, a dischargeelectrode extending therethrough, means for constricting the dew of gasadjacent the electrode and means for preventing a disruptive dischargefrom the discharge electrode to said constricting means at voltagesbelow the normal critical voltage. 5

6. in an electric precipitator the combination ofa treater chamber, adischarge electrode extending therethrough, means for constricting theflow of gas adjacent the discharge electrode, said discharge electrodecomprising active electrode sections at both sides of the constrictingmeans an insulator link between said sections adja cent saidconstriction.

7. in an electric precipitator the combination of a trcater chamher, inchamher for symmetrically constricting flow of gas therethrough,discharge I trode sections at both sides of the cones cting means and aninsulator for 1 1 calm chanically connecting the discharge electrodesections adjacent said constricting means. V

8. In an electric precipitator the combination of a treater chamber,damping vanes located in said chamber laterally of the axis of thechamber, dischargeelectrode sections at both sides of the damping vanesand an insulator link between said damping vanes formechanicallyconnecting the discharge electrode sections.

9. In an electric precipitator the combination of a treater chamben adischarge electrode extending through the chamber, a diaphragmsymmetrically located about the axisof the chamber, said dischargeelectrode comprising active sections at both sides of the diaphragm andan insulator extending through the diaphragm aperture for connecting theelectrode sections.

In testimony whereof I aflix my signature in presence of two witnesses.0

WILLIAM W. STRQNG,

Witness:

RUTH M. Hnrrnnrmenn, G. W. Sroorrnn.

